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Author Topic:   Speed of Light
Son Goku
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Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


Message 54 of 268 (538092)
12-03-2009 2:23 PM
Reply to: Message 47 by Viv Pope
12-02-2009 9:07 AM


Special Relativity and geometry
Hey Viv Pope,
I just want to comment on one element of your post:
In the 1960s Professor Herman Bondi and I were among the first – if not actually THE first – to point out the logical redundancy of the ‘velocity’ interpretation of c. In his words:

Any attempt to measure the velocity of light is . . . not an attempt at measuring the velocity of light but an attempt at ascertaining the length of the standard metre in Paris in terms of time-units.

This was in Bondi’s book Assumption and Myth in Physical Theory, (Cambridge University Press, 1965. p.28). Both Bondi and I concurred, independently, that Relativity could be much more simply expressed in terms which omitted, entirely, the customary ‘;velocity’ interpretation of the constant, c. For him it was sufficient, as he said to make it simpler and easier to teach Relativity to students, in terms of what he called his ‘K-calculus’ approach to Relativity. For me, this new interpretation of c as a pure constant marked the point of departure for a whole new different paradigm approach to physics which, as Bondi said, he would leave to me to develop ‘with his blessing’.


Bondi appears to be taking c as the relationship of temporal units of measurement and spatial units of measurement. In other words it tells you how many spatial units (meters) are in the standard temporal unit (1 second).

If this is the case, then this is already well known. As cavediver has already pointed out this is implicit in the geometric way of presenting relativity first worked out by Hermann Minkowski.


This message is a reply to:
 Message 47 by Viv Pope, posted 12-02-2009 9:07 AM Viv Pope has replied

Replies to this message:
 Message 55 by Percy, posted 12-03-2009 3:21 PM Son Goku has replied
 Message 66 by Viv Pope, posted 12-04-2009 9:33 AM Son Goku has replied

  
Son Goku
Member
Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


Message 56 of 268 (538102)
12-03-2009 4:05 PM
Reply to: Message 55 by Percy
12-03-2009 3:21 PM


Re: Special Relativity and geometry
Note that I'm not arguing that the observation isn't valuable. What I'm trying to point out is that if this observation about c is truly valuable then it is possibly in a way that isn't obvious to the layperson (or at least to me) and needs to be explained. Otherwise you and CaveDiver and Viv Pope may as well be speaking ancient Greek as far as the rest of us are concerned.

Sorry for the lack of explanation perhaps the following will help.
In everyday speech and even everyday science, we have two seperate measurements for space and time. Space is measured in meters and time is measured in seconds. However in relativity time and space are supposed to become connected, so they shouldn't really have different units. So you have to ask yourself "How many meters is a second worth?", that is when I sit around for one second how many meters have I moved in the temporal direction.

c is basically the constant for that conversion. It says that there are 300,000,000 meters in one second.

To give you an idea of what this implies, when I walk one meter to the left in one second, I have moved one meter in space and three hundred million meters in time. Apply this to any type of motion you can think of and you'll see that most things move much more in time than they do in space.

Light is special because it moves equally in both. That is, it moves 300,000,000 meters in space for every 300,000,000 meters in time. Or if we convert back into everyday units, 300,000,000 meters in one second. Which is c.


This message is a reply to:
 Message 55 by Percy, posted 12-03-2009 3:21 PM Percy has replied

Replies to this message:
 Message 57 by Percy, posted 12-03-2009 5:08 PM Son Goku has replied

  
Son Goku
Member
Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


Message 60 of 268 (538140)
12-04-2009 5:40 AM
Reply to: Message 57 by Percy
12-03-2009 5:08 PM


Re: Special Relativity and geometry
There's something I still must not be grasping, but I understand the explanation and maybe the significance will become apparent to me over time.

Well to tell the truth it is or isn't significant depending on what you think. Personally I would view it as a interesting fact, it gives you an idea of the size of things like minutes or seconds. Periods of time we think of as short. For example a minute is actually 18 million kilometers, I think it's incredible that I've traveled that far in one direction just by sitting around.

However in another way it isn't truly significant. It doesn't lead to any great insight or anything, because to know it you'd have to already know special relativity. So I would say it's an interesting consequence of relativity, not a fundamental insight in and of itself.

But more importantly, most physicists would agree with this particular observation by Viv Pope

Yes, they would.

but doesn't Viv Pope believe that most physicists fail to appreciate how truly significant, revolutionary even, this observation is? If so, what's he see in this observation that they don't?

I believe (I'm not sure) that Viz Pope is saying that it leads to a more geometrical view of relativity, which he believes is incredible news. However any physicist would say we have had a geometrical view of relativity for (at this point) 102 years.

The phrase "a geometrical view of relativity" is a bit vague so let me try to explain that. When Einstein published the first few papers on special relativity, he wrote it as a physical theory. That is to say, he expressed it as relationships between energy and mass and velocities as viewed by different observers. Basically, from a mathematical point of view it looked like Newton's mechanics just with different formulas.

However in 1907 Hermann Minkowski (who taught Einstein at university) realised that all of Einstein's special relativity could be rewritten in a much simpler form. He basically showed that all of special relativity followed just by assuming that time and space formed one big "thing" called spacetime and that spacetime had a specific shape or geometry. Hence everything in Einstein's theory was just a consequence of this new geometry.

This is the way physicists view special relativity today. In fact you have to, because you need to see that special relativity is really about the geometry of spacetime in order to get to general relativity.


This message is a reply to:
 Message 57 by Percy, posted 12-03-2009 5:08 PM Percy has replied

Replies to this message:
 Message 62 by Percy, posted 12-04-2009 6:35 AM Son Goku has taken no action

  
Son Goku
Member
Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


Message 90 of 268 (538375)
12-06-2009 7:21 AM
Reply to: Message 66 by Viv Pope
12-04-2009 9:33 AM


Re: Special Relativity and geometry
Okay, I'm not really understanding any of this.
Could you, in one or two lines, list one difference between what you are saying and standard relativity?
Currently I see no difference between what you are saying and what Minkowski discovered, unless Percy is right and you're saying "that light doesn't travel from our perspective, either".

Please a simple paragraph summing up one little component of what you're proposing would be helpful.


This message is a reply to:
 Message 66 by Viv Pope, posted 12-04-2009 9:33 AM Viv Pope has replied

Replies to this message:
 Message 101 by Viv Pope, posted 12-06-2009 11:43 AM Son Goku has replied
 Message 102 by Viv Pope, posted 12-06-2009 11:44 AM Son Goku has taken no action

  
Son Goku
Member
Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


Message 91 of 268 (538376)
12-06-2009 7:32 AM
Reply to: Message 70 by Viv Pope
12-04-2009 1:20 PM


Re: Moderator On Duty
The difference between what we do and what Minkowski did, scientifically speaking, is to show that Einstein’s Second Axiom concerning the ‘constant velocity of light in vacuo’ is both mathematically and conceptually redundant. One might validly argue that this, implicitly, is what Minkowski did, and that may well be true.

First of all, it is explicitly what Minkowski did. He showed that all of relativity followed simply from postulating that we live in a four dimensional world with a certain geometry.
Also I've been reading through your website and what I've seen indicates that you are simply replicating, with a lot more words, some aspects of what Minkowski did in a 58 page report 102 years ago.

This message is a reply to:
 Message 70 by Viv Pope, posted 12-04-2009 1:20 PM Viv Pope has replied

Replies to this message:
 Message 104 by Viv Pope, posted 12-06-2009 12:38 PM Son Goku has replied

  
Son Goku
Member
Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


Message 103 of 268 (538400)
12-06-2009 12:14 PM
Reply to: Message 101 by Viv Pope
12-06-2009 11:43 AM


Re: Special Relativity and geometry
Viv Pope writes:

The radical difference between my relativity and the standard Minkowski-Einstein one is that it makes no reference whatsoever to ‘light velocity’, as per Einstein’s Second Postulate of Relativity. This means that it dispenses with the whole historical rigmarole of ‘light-waves’, ‘light corpuscles’, ‘fields’ (electrostatic, magnetostatic or gravitational), nuclear (strong, weak, electroweak) or whatever.


This, my uniquely different approach to relativity achieves by dispensing, at a stroke, with ‘fields’ altogether.

Well Minkowski has already done all this. His formulation of relativity doesn't need fields, light-waves or light corpuscles either. He described relativity as a consequence of pure geometry, hence what you have done is nothing new.
Further, a reading of your website indicates the same. What is correct on the website isn't new and what is "new" isn't correct. For instance you claim:
Viv Pope on his website writes:

In Einstein's theory the 'special' and 'general' aspects of relativity are separate


which is completely false. Special Relativity is a special case of General Relativity. Minkowski spacetime, which is the geometric way of describing special relativity, becomes just one solution of the equations of general relativity. They are certainly not seperate.

This message is a reply to:
 Message 101 by Viv Pope, posted 12-06-2009 11:43 AM Viv Pope has replied

Replies to this message:
 Message 114 by Viv Pope, posted 12-08-2009 5:37 AM Son Goku has taken no action

  
Son Goku
Member
Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


Message 105 of 268 (538405)
12-06-2009 12:56 PM
Reply to: Message 104 by Viv Pope
12-06-2009 12:38 PM


Re: Moderator On Duty
Viv Pope writes:

Now why on earth would I do that? What a waste of fifty years study that would be!

Your insistence on this, which is tantamount to a charge of plagiarism, is ridiculous.


I'm not accusing you of plagarising Minkowski. I just think that maybe what you are proposing isn't that new or incredible. It's just a very wordy rederivation of some of what Minkowski did.

Viv Pope writes:

Are you in the habit of regarding anyone presenting something new as necessarily a shyster? Can't you credit someone with some new intelligence and honesty?


No, I'm okay with new things. In fact what I'm saying is that what you are doing is old. Something accomplished at the turn of the century. Of course that is in the cases where you are correct. Some of what you claim is known to be false.

Just for one thing, if, as you say, you read my website (which one?)

The Web Site of Science-Philosopher Viv Pope, at http://www.vivpope.org/

This message is a reply to:
 Message 104 by Viv Pope, posted 12-06-2009 12:38 PM Viv Pope has taken no action

  
Son Goku
Member
Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


(1)
Message 256 of 268 (671600)
08-28-2012 4:12 AM
Reply to: Message 245 by David Carroll
08-24-2012 11:59 PM


Re: c & t
Or - as is my contention - it could possibly mean that the speed of light has changed over time, or possibly over space.

I should say that in modern physics, especially after relativity, c is not considered a fundamental constant. This is because c can be eliminated from equations by a simple change of units. More correctly however c arises because human being measure time and space differently.
We measure the x,y,z coordinates with one unit, meters and the t coordinate with completely separate unit, seconds. Both should really be measured with meters. A second is just 300,000,000 meters in time.

However if we keep our standard units equations have to be fitted with a factor, c = 300,000,000 m/s, in order to account for this mismatch of units.

The only physically real parameter associated with light is alpha, the fine structure constant, measuring how much light couples to matter. There has yet to be an experimental test or cosmological observation which shows statistically significant variation in alpha. Also if alpha varied, there should be an alpha particle, which we should have detected already if it existed, but we haven't.


This message is a reply to:
 Message 245 by David Carroll, posted 08-24-2012 11:59 PM David Carroll has taken no action

Replies to this message:
 Message 257 by Coragyps, posted 08-28-2012 8:52 AM Son Goku has replied

  
Son Goku
Member
Posts: 1207
From: Ireland
Joined: 07-16-2005
Member Rating: 5.2


(3)
Message 258 of 268 (671626)
08-28-2012 1:53 PM
Reply to: Message 257 by Coragyps
08-28-2012 8:52 AM


Re: c & t
A different alpha particle, you meant to say?

Ah, yes! You're right of course. I could say a fine-structure particle. Alpha is often called the fine-structure constant.

The reason for this particle is that if something is no longer just a number, if it has different values at different points in space and time, then it is a field. And under quantum mechanics all fields are associated with particles.

'Course, you real physicists likely don't regard two protons bound to two neutrons as a particle, anyway. More like a dozen?

Actually that question has two different answers!

Firstly an alpha particle could be considered a collection of twelve quarks as you said.

However quarks don't actually exist at the current temperature of the universe. Quarks only existed early on in the universe's history. When we say that the proton is made out of quarks we actually mean that if the universe became extremely hot again the proton would become three quarks, it's not actually made out of them. It also acts a lot like it's a collection of three quarks in certain experiments. However technically there are no quarks inside a proton.


This message is a reply to:
 Message 257 by Coragyps, posted 08-28-2012 8:52 AM Coragyps has taken no action

  
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